Try to make the best of it. We turn to south africa. 91 world leaders including four american presidents attended tomorrow's memorial service. President obama and the first lady are flying there today, joined on air force one by george w. Bush. Terry moran has more. Reporter: This is a huge week for this country and people around the world. South africa is saying a long andifully affectionate farewell to the man that just about everybody here calls tata, father. Candles and flowers at nelson mandela's house. A people's spontaneous tribute. At the south african parliament, a special session this morning. At the fnb stadium, 91 world leaders are expected to join 90,000 ordinary south africani is in a massive and historic memorial tomorrow. Over the weekend, churches filled with songs and prayer in memory and gratitude for mandela's life. &#9834; Nelson mandela nelson mandela &#9834; Reporter: But to grasp the true measure of what he means to south africa, listen to the children of this land. He's the one who fought for our freedom. Reporter: Mandela, who in his 27 years in prison, was denied the chance to raise his own children, reached out to kids here with a special flair and joy. Because of him, they dream big here now. What do you want to be when you grow up? I want to be a lawyer. Reporter: A lawyer. Excellent. I want to be a pilot. Reporter: A pilot. Police? A nation transformed. Mandela's body will lie in state right back there in the union building. The center of government. Once the center of apartheid's oppression. And this week, the site of the ultimate honor for the man who brought down apartheid. A massive memorial service. 90 world leaders. A massive security challenge, too. Reporter: Huge challenge for this country, george. We're already seeing signs that it is beginning -- the preparations for road closures. And the skies overjohannesburg restricted air space. One big concern, they have is turnout. That stadium holds 95,000 people. They're expecting far more to show up. They're rapidly trying to find overflow areas. There could be some chaos tomorrow. As one official said, we can't turn people away. They want to be there. Thank you, terry. Let's get today's other top

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